MOULTING HABITS OF SPIDERS. 105 
skin recovered from the burrow it had succeeded in casting them all off 
without any mutilation. The spring of 1887 was a backward one, and I 
experienced great difficulty in procuring insects for food from 
ee the immediate neighborhood. The annual supply of grasshop- 
earl pers and locusts upon which I had relied came very late. Per- 
ment. p 
haps had the spider been strengthened by a few weeks generous 
feeding previous to its last moult it might still have been alive. 
VII. 
With each moult spiders undergo a change in color and patterns more 
or less decided. Some species have such neutral colors and are so uni- 
formly marked that the differences are not decided; but some 
undergo such decided changes that different species have been 
established for the same spider upon specimens taken after differ- 
ent moulting periods. In some species the colors and markings of the 
youngling, after the first moult or two, fairly represent the markings at 
maturity; in others the difference is so great between the two stages of life 
that it is quite impossible to identify young individuals, or distinguish the 
young of several species with accuracy. 
Among the young of Lycosa and Attus, according to Wagner, these mod- 
ifications are effected with the female and male so equally and uniformly 
during the first four or five moults, and with Trochosa during the first six 
Color 
Changes. 
-or seven moults, that one is scarcely able to distinguish the sex. With the 
final moults these distinctions become more and more marked, though not 
always to the same degree. The differences in relative length of legs and 
in the shape of the palps also begin to appear; for example, the male 
Trochosa singoriensis at the seventh moult equals in body size and rela- 
tive length of the legs those of the female at the sixth moult. ‘The same 
is true of Attus, 
Among Orbweavers generally, and in spiders of various tribes observed, 
the change in color (and in form also) is most decided in the males; that 
_ is, the young male carries the typical colors and general shape 
Sh beg ™ of the adult female; the younglings of both sexes after the 
initial moults resemble each other perfectly, and tend to resemble 
the adult female. Thus the young male of Dictyna philoteichous bears a 
close likeness if color and pattern to the adult female; but after final moult 
the difference in color is quite marked, as well as in shape of palps and 
contour of body. 
Professor Peckham! finds a close resemblance between birds and_spi- 
ders in their moulting changes, and his special studies of the Attide are 
1 Occasional Papers, Nat. Hist. Soc., Wisconsin, Vol. I., 1889, page 16, George W. and 
Elizabeth G. Peckham. 
